Author Contributions
Conceptualization, J.A.C, B.R.J., M.A.J., S.E.W., S.C.; Methodology, J.A.C, B.R.J., M.A.J., S.E.W., S.C.; Software, S.C.; Validation, J.A.C, B.R.J., M.A.J., S.E.W., S.C.; Formal Analysis, J.A.C, B.R.J., M.A.J., S.E.W., S.C.; Investigation, J.A.C, B.R.J., M.A.J., S.E.W., S.C.; Resources, J.A.C, B.R.J., M.A.J., S.E.W., S.C.; Data Curation, J.A.C, B.R.J., M.A.J., S.E.W., S.C.; Writing-Original Draft Preparation, J.A.C, B.R.J., M.A.J., S.E.W., S.C.; Writing-Review & Editing, JJ.A.C, B.R.J., M.A.J., S.E.W., S.C.; Visualization, J.A.C, B.R.J., M.A.J., S.E.W., S.C.; Supervision, J.A.C.; Project Administration, J.A.C.; Funding Acquisition, J.A.C, B.R.J., M.A.J., S.E.W.
Figure 1.
(A) Collapsed mussel beds in eastern Maine, USA. Shell hash is the primary component of the surface of the beds pictured here. (B) The four bottom cover types commonly observed at robust and collapsed mussel beds.
Figure 1.
(A) Collapsed mussel beds in eastern Maine, USA. Shell hash is the primary component of the surface of the beds pictured here. (B) The four bottom cover types commonly observed at robust and collapsed mussel beds.
Figure 2.
(A) Study site at Carrying Place Cove, Harrington, Maine, USA. Longest fetch is from the east, indicated by red arrow. (B) Wind condition index (Day 1 > Day 3 > Day 2) created by combining wind velocity and fetch values when the bottom was covered with water during the three days of the investigation. Map data copyright 2015 Google.
Figure 2.
(A) Study site at Carrying Place Cove, Harrington, Maine, USA. Longest fetch is from the east, indicated by red arrow. (B) Wind condition index (Day 1 > Day 3 > Day 2) created by combining wind velocity and fetch values when the bottom was covered with water during the three days of the investigation. Map data copyright 2015 Google.
Figure 3.
(A) Mass values of silt-clay, fine sand, and coarse material in traps. For clarity, error bars are presented only for total sediment mass. (B) Percent organic matter. Values are mean ± 1 SE. Live = live mussels, Whole = whole shells, Frag = fragmented shells, Bare = bare sediment. 1 = Day 1, 2 = Day 2, 3 = Day 3.
Figure 3.
(A) Mass values of silt-clay, fine sand, and coarse material in traps. For clarity, error bars are presented only for total sediment mass. (B) Percent organic matter. Values are mean ± 1 SE. Live = live mussels, Whole = whole shells, Frag = fragmented shells, Bare = bare sediment. 1 = Day 1, 2 = Day 2, 3 = Day 3.
Figure 4.
(A) Meiofauna values for number of taxa and H’ in traps. (B) Meiofauna absolute dispersal rates (ADR). (C) Meiofauna relative dispersal rates (RDR). (D) Meiofauna bulk dispersal rates (BDR). Values are mean ± 1 SE. Live = Live mussels, Whole = Whole shells, Frag = Fragmented shells, Bare = Bare sediment. 1 = Day 1, 2 = Day 2, 3 = Day 3.
Figure 4.
(A) Meiofauna values for number of taxa and H’ in traps. (B) Meiofauna absolute dispersal rates (ADR). (C) Meiofauna relative dispersal rates (RDR). (D) Meiofauna bulk dispersal rates (BDR). Values are mean ± 1 SE. Live = Live mussels, Whole = Whole shells, Frag = Fragmented shells, Bare = Bare sediment. 1 = Day 1, 2 = Day 2, 3 = Day 3.
Figure 5.
Nonmetric multidimensional scaling (nMDS) plots for traps: (A) meiofauna, (B) macrofauna.
Figure 5.
Nonmetric multidimensional scaling (nMDS) plots for traps: (A) meiofauna, (B) macrofauna.
Figure 6.
(A) Macrofauna values for number of taxa and H’ in traps. (B) Macrofauna absolute dispersal rates (ADRs). (C) Meiofauna bulk dispersal rates (BDRs). Values are mean ± 1 SE. Live = live mussels, Whole = whole shells, Frag = fragmented shells, Bare = bare sediment. 1 = Day 1, 2 = Day 2, 3 = Day 3.
Figure 6.
(A) Macrofauna values for number of taxa and H’ in traps. (B) Macrofauna absolute dispersal rates (ADRs). (C) Meiofauna bulk dispersal rates (BDRs). Values are mean ± 1 SE. Live = live mussels, Whole = whole shells, Frag = fragmented shells, Bare = bare sediment. 1 = Day 1, 2 = Day 2, 3 = Day 3.
Table 1.
ANOVA results for sediment in traps: mass values and percent total organic material. Transformations indicated where applied. Significant differences (P < 0.05) are in bold and Student-Newman-Keuls (SNK) results are presented. NAH = no alternative hypothesis; the two groups with the largest and smallest means within the factor were significantly different, and no further resolution among the groups in that factor could be determined. L = live mussels, F = fragmented shells. D1 = Day 1, D2 = Day 2, D3 = Day 3.
Table 1.
ANOVA results for sediment in traps: mass values and percent total organic material. Transformations indicated where applied. Significant differences (P < 0.05) are in bold and Student-Newman-Keuls (SNK) results are presented. NAH = no alternative hypothesis; the two groups with the largest and smallest means within the factor were significantly different, and no further resolution among the groups in that factor could be determined. L = live mussels, F = fragmented shells. D1 = Day 1, D2 = Day 2, D3 = Day 3.
| | Sediment |
---|
| | Coarse (g) | Fine (g) | Silt-Clay (g) |
Source | DF | F | P | F | P | F | P |
Day | 2 | 2.18 | 0.194 | 7.13 | 0.026 | 2.47 | 0.165 |
Cover | 3 | 2.05 | 0.134 | 0.70 | 0.560 | 5.26 | 0.006 |
Day × Cover | 6 | 0.70 | 0.652 | 0.92 | 0.500 | 1.35 | 0.275 |
Residual | 24 | | | | | | |
Total | 35 | | | | | | |
Transformation | | Ln(x + 1) | | Ln(x + 1) |
SNK Day | | | | D1 > D2 = D3 | | |
SNK Cover | | | | | | NAH (L > F) |
| | Total (g) | Organic Matter (%) | | |
Source | DF | F | P | F | P | | |
Day | 2 | 7.01 | 0.027 | 11.34 | 0.0003 | | |
Cover | 3 | 1.21 | 0.328 | 0.51 | 0.680 | | |
Day × Cover | 6 | 0.68 | 0.664 | 1.02 | 0.438 | | |
Residual | 24 | | | | | | |
Total | 35 | | | | | | |
Transformation | | Ln(x + 1) | Ln(x + 1) | | |
SNK Day | | D1 > D3 = D2 | D3 > D1 > D2 | | |
SNK Cover | | | | | | | |
Table 2.
ANOVA results for meiofauna in traps: number of species, H’, and absolute dispersal rates (ADR). Transformations indicated where applied. Significant differences (P < 0.05) are in bold and SNK results are presented. NAH = no alternative hypothesis; the two groups with the largest and smallest means within the factor were significantly different, and no further resolution among the groups in that factor could be determined. L = live mussels, W = whole shells, F = fragmented shells, B = bare sediment. D1 = Day 1, D2 = Day 2, D3 = Day 3.
Table 2.
ANOVA results for meiofauna in traps: number of species, H’, and absolute dispersal rates (ADR). Transformations indicated where applied. Significant differences (P < 0.05) are in bold and SNK results are presented. NAH = no alternative hypothesis; the two groups with the largest and smallest means within the factor were significantly different, and no further resolution among the groups in that factor could be determined. L = live mussels, W = whole shells, F = fragmented shells, B = bare sediment. D1 = Day 1, D2 = Day 2, D3 = Day 3.
| | Meiofauna |
---|
| | No. of Taxa | H’ | Total Assemblage |
Source | DF | F | P | F | P | F | P |
Day | 2 | 0.72 | 0.495 | 4.17 | 0.028 | 6.36 | 0.006 |
Cover | 3 | 1.20 | 0.333 | 5.70 | 0.004 | 4.34 | 0.014 |
Day × Cover | 6 | 0.54 | 0.772 | 2.32 | 0.066 | 0.29 | 0.936 |
Residual | 24 | | | | | | |
Total | 35 | | | | | | |
Transformation | | | | | | Ln(x + 1) |
SNK Day | | | | D1 > D2 = D3 | D1 = D3 > D2 |
SNK Cover | | | | NAH (B > L) | W = L = B > F |
| | Copepods | Nematodes | Foraminiferans |
Source | DF | F | P | F | P | F | P |
Day | 2 | 3.72 | 0.039 | 10.99 | 0.0004 | 3.57 | 0.044 |
Cover | 3 | 3.67 | 0.026 | 4.04 | 0.019 | 4.39 | 0.013 |
Day × Cover | 6 | 0.52 | 0.787 | 0.38 | 0.886 | 1.47 | 0.229 |
Residual | 24 | | | | | | |
Total | 35 | | | | | | |
Transformation | | Ln(x + 1) | Ln(x + 1) | Ln(x + 1) |
SNK Day | | D1 = D3 > D2 | D1 > D3 = D2 | NAH (D1 > D3) |
SNK Cover | | W = L = B > F | NAH (W > F) | NAH (B > F) |
Table 3.
PERMANOVA results for meiofauna and macrofauna in traps. Significant differences (P < 0.05) are in bold. For parameters with significant differences among Days or Cover Types, the mean Bray-Curtis dissimilarity values (%) within and among Days and Cover Types are presented. L = Live mussels, W = Whole shells, F = Fragmented shells, B = Bare sediment. D1 = Day 1, D2 = Day 2, D3 = Day 3.
Table 3.
PERMANOVA results for meiofauna and macrofauna in traps. Significant differences (P < 0.05) are in bold. For parameters with significant differences among Days or Cover Types, the mean Bray-Curtis dissimilarity values (%) within and among Days and Cover Types are presented. L = Live mussels, W = Whole shells, F = Fragmented shells, B = Bare sediment. D1 = Day 1, D2 = Day 2, D3 = Day 3.
| | Meiofauna | Macrofauna |
---|
Source | DF | F | P | F | P |
Day | 2 | 3.69 | 0.006 | 1.34 | 0.179 |
Cover | 3 | 3.03 | 0.011 | 1.35 | 0.153 |
Day × Cover | 6 | 0.56 | 0.934 | 1.41 | 0.076 |
Residual | 24 | | | | |
Total | 35 | | | | |
| | Within Days: | | |
| | D1 | 40.41 | | |
| | D2 | 48.92 | | |
| | D3 | 41.65 | | |
| | Among Days: | | |
| | D1 vs. D2 | 53.39 | | |
| | D1 vs. D3 | 43.87 | | |
| | D2 vs. D3 | 47.84 | | |
| | Within Cover Types: | | |
| | L | 45.32 | | |
| | W | 47.15 | | |
| | F | 49.51 | | |
| | B | 30.04 | | |
| | Among Cover Types: | | |
| | B vs. L | 38.69 | | |
| | B vs. W | 43.06 | | |
| | B vs. F | 52.83 | | |
| | L vs. W | 48.8 | | |
| | L vs. F | 56.21 | | |
| | W vs. F | 48.66 | | |
Table 4.
ANOVA results for meiofauna in traps: relative dispersal rates (RDR). Transformations indicated where applied. Significant differences (P < 0.05) are in bold and SNK results are presented. NAH = no alternative hypothesis; the 2 groups with the largest and smallest means within the factor were significantly different, and no further resolution among the groups in that factor could be determined. L = Live mussels, W = Whole shells, F = Fragmented shells, B = Bare sediment. D1 = Day 1, D2 = Day 2, D3 = Day 3.
Table 4.
ANOVA results for meiofauna in traps: relative dispersal rates (RDR). Transformations indicated where applied. Significant differences (P < 0.05) are in bold and SNK results are presented. NAH = no alternative hypothesis; the 2 groups with the largest and smallest means within the factor were significantly different, and no further resolution among the groups in that factor could be determined. L = Live mussels, W = Whole shells, F = Fragmented shells, B = Bare sediment. D1 = Day 1, D2 = Day 2, D3 = Day 3.
| | Meiofauna |
---|
| | Total Assemblage | Copepods |
Source | DF | F | P | F | P |
Day | 2 | 2.32 | 0.120 | 1.40 | 0.267 |
Cover | 3 | 5.21 | 0.007 | 3.29 | 0.038 |
Day × Cover | 6 | 1.02 | 0.437 | 0.96 | 0.474 |
Residual | 24 | | | | |
Total | 35 | | | | |
Transformation | | Ln(x + 1) | Ln(x + 1) |
SNK Day | | | | | |
SNK Cover | | W > L = F = B | W > F = L = B |
| | Nematodes | Foraminiferans |
Source | DF | F | P | F | P |
Day | 2 | 1.75 | 0.196 | 4.06 | 0.030 |
Cover | 3 | 3.00 | 0.051 | 3.87 | 0.022 |
Day × Cover | 6 | 0.57 | 0.752 | 0.89 | 0.521 |
Residual | 24 | | | | |
Total | 35 | | | | |
Transformation | | | | | |
SNK Day | | | | D1 > D3 = D2 |
SNK Cover | | | | NAH (W > F) |
Table 5.
ANOVA results for meiofauna in traps: bulk dispersal rates (BDRs). Transformations indicated where applied. Significant differences (P < 0.05) are in bold. For parameters with significant differences, the SNK results are presented. NAH = no alternative hypothesis; the two groups with the largest and smallest means within the factor were significantly different, and no further resolution among the groups in that factor could be determined. F = fragmented shells, B = bare sediment. D1 = Day 1, D2 = Day 2, D3 = Day 3.
Table 5.
ANOVA results for meiofauna in traps: bulk dispersal rates (BDRs). Transformations indicated where applied. Significant differences (P < 0.05) are in bold. For parameters with significant differences, the SNK results are presented. NAH = no alternative hypothesis; the two groups with the largest and smallest means within the factor were significantly different, and no further resolution among the groups in that factor could be determined. F = fragmented shells, B = bare sediment. D1 = Day 1, D2 = Day 2, D3 = Day 3.
| | Meiofauna |
---|
| | Total Assemblage | Copepods |
Source | DF | F | P | F | P |
Day | 2 | 0.98 | 0.389 | 3.77 | 0.038 |
Cover | 3 | 2.22 | 0.112 | 2.20 | 0.114 |
Day × Cover | 6 | 0.59 | 0.734 | 0.81 | 0.571 |
Residual | 24 | | | | |
Total | 35 | | | | |
Transformation | | | | | |
SNK Day | | | | D2 = D3 > D1 |
SNK Cover | | | | | |
| | Nematodes | Foraminiferans |
Source | DF | F | P | F | P |
Day | 2 | 0.62 | 0.544 | 0.92 | 0.412 |
Cover | 3 | 3.61 | 0.028 | 1.40 | 0.268 |
Day × Cover | 6 | 0.29 | 0.938 | 1.02 | 0.438 |
Residual | 24 | | | | |
Total | 35 | | | | |
Transformation | | Ln(x + 1) | Ln(x + 1) |
SNK Day | | | | | |
SNK Cover | | NAH (B > F) | | |
Table 6.
ANOVA results for macrofauna in traps: number of species, H’, and absolute dispersal rates (ADRs). Transformations indicated where applied.
Table 6.
ANOVA results for macrofauna in traps: number of species, H’, and absolute dispersal rates (ADRs). Transformations indicated where applied.
| | Macrofauna |
---|
| | No. of Species | H’ | Total Assemblage |
Source | DF | F | P | F | P | F | P |
Day | 2 | 1.61 | 0.221 | 0.98 | 0.391 | 1.57 | 0.229 |
Cover | 3 | 0.81 | 0.502 | 0.30 | 0.825 | 1.34 | 0.284 |
Day × Cover | 6 | 0.34 | 0.910 | 0.24 | 0.958 | 0.49 | 0.809 |
Residual | 24 | | | | | | |
Total | 35 | | | | | | |
Transformation | | | | | Ln(x + 1) |
| | Oligochaetes | Non-Oligochaetes | | |
Source | DF | F | P | F | P | | |
Day | 2 | 1.96 | 0.163 | 1.88 | 0.175 | | |
Cover | 3 | 1.29 | 0.302 | 0.48 | 0.698 | | |
Day × Cover | 6 | 0.76 | 0.605 | 0.24 | 0.959 | | |
Residual | 24 | | | | | | |
Total | 35 | | | | | | |
Transformation | | Ln(x + 1) | | | | |
Table 7.
ANOVA results for macrofauna in traps: bulk dispersal rates (BDRs). Transformation indicated where applied. Significant differences (P < 0.05) are in bold and SNK results are presented. D1 = Day 1, D2 = Day 2, D3 = Day 3.
Table 7.
ANOVA results for macrofauna in traps: bulk dispersal rates (BDRs). Transformation indicated where applied. Significant differences (P < 0.05) are in bold and SNK results are presented. D1 = Day 1, D2 = Day 2, D3 = Day 3.
| | Macrofauna Parameter |
---|
| | N | Oligochaetes | Non-Oligochaetes |
Source | DF | F | P | F | P | F | P |
Day | 2 | 4.65 | 0.020 | 0.94 | 0.405 | 4.91 | 0.016 |
Cover | 3 | 2.09 | 0.128 | 1.68 | 0.197 | 0.62 | 0.612 |
Day × Cover | 6 | 1.08 | 0.403 | 0.91 | 0.502 | 0.64 | 0.699 |
Residual | 24 | | | | | | |
Total | 35 | | | | | | |
Transformation | | | | Ln(x + 1) | | |
SNK Day | | D2 > D3 = D1 | | | D2 > D3 = D1 |